org.javamoney.moneta.spi

Interface LoaderService

All Known Implementing Classes:

DefaultLoaderService

public interface LoaderService

This interface defines an updatable/reloadable data cache for providing data sources that are updatable by any remote URLs. Initial version are loaded from the classpath, or other fallback URL.

This class is used for managing/updating/reloading of data sources, e.g. data streams for exchange rates, additional currency data, historical currency data and so on.

Note: this class is implementation specific and not part of the official JSR's API.

Author:

Anatole Tresch

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	LoaderService.LoaderListener Callback that can be registered to be informed, when a data item was loaded/updated or reset.
static class	LoaderService.UpdatePolicy Platform RI: The update policy defines how and when the LoaderService tries to update the local cache with newest version of the registered data resources, accessing the configured remote URLs.

Method Summary

Methods

Modifier and Type	Method and Description
void	addLoaderListener(LoaderService.LoaderListener l, String... resourceIds) Add a LoaderService.LoaderListener callback that is informed when a data resource was update from remote, or reset.
InputStream	getData(String resourceId) Access the input stream of the given data resource.
Set<String>	getResourceIds() Get a Set of all registered data resource identifiers.
Map<String,String>	getUpdateConfiguration(String resourceId) Get the update configuration for the given dataId.
LoaderService.UpdatePolicy	getUpdatePolicy(String resourceId) Get the LoaderService.UpdatePolicy in place for the given dataId.
boolean	isResourceRegistered(String resourceId) Allows to check if a data resource with the given dataId is registered.
boolean	loadData(String resourceId) Explicitly triggers the remote loading of the registered data, regardless of its current LoaderService.UpdatePolicy configured.
Future<Boolean>	loadDataAsync(String resourceId) Explicitly asynchronously triggers the remote loading of the registered data, regardless of its current LoaderService.UpdatePolicy configured.
boolean	loadDataLocal(String resourceId) Explicitly triggers the loading of the registered data, regardless of its current LoaderService.UpdatePolicy configured, from the fallback/local resource.
void	registerData(String resourceId, LoaderService.UpdatePolicy updatePolicy, Map<String,String> properties, URL backupResource, URL... resourceLocations) Programmatically registers a remote resource resourceLocation, backed up by a classpath resource backupResource, reachable as dataId.
void	removeLoaderListener(LoaderService.LoaderListener l, String... resourceIds) Remove a registered LoaderService.LoaderListener callback.
void	resetData(String resourceId) Explicitly triggers the reset (loading of the registered data from the classpath backup resource).

Method Detail

registerData

void registerData(String resourceId,
                LoaderService.UpdatePolicy updatePolicy,
                Map<String,String> properties,
                URL backupResource,
                URL... resourceLocations)

Programmatically registers a remote resource resourceLocation, backed up by a classpath resource backupResource, reachable as dataId.

Parameters:

resourceId - The unique identifier of the resource that must also be used for accessing the resource, not null.

resourceLocations - The remote resource locations, not null.

backupResource - The backup resource location in the classpath, not null.

getUpdatePolicy

LoaderService.UpdatePolicy getUpdatePolicy(String resourceId)

Get the LoaderService.UpdatePolicy in place for the given dataId.

Parameters:

resourceId - the resource's id, not null

Returns:

the LoaderService.UpdatePolicy, not null

Throws:

IllegalArgumentException - if no such dataId is available.

getUpdateConfiguration

Map<String,String> getUpdateConfiguration(String resourceId)

Get the update configuration for the given dataId.

Parameters:

resourceId - the dataId, not null

Returns:

the update configuration properties, not null

Throws:

IllegalArgumentException - if no such dataId is available.

addLoaderListener

void addLoaderListener(LoaderService.LoaderListener l,
                     String... resourceIds)

Add a LoaderService.LoaderListener callback that is informed when a data resource was update from remote, or reset. Passing an empty String or null sa dataId allows to register a listener for all data resources registered. loadData(String) resetData(String)

Parameters:

resourceIds - The unique identifiers of the resource, not null.

l - The listener to be added

See Also:

removeLoaderListener(LoaderListener,String...)

removeLoaderListener

void removeLoaderListener(LoaderService.LoaderListener l,
                        String... resourceIds)

Remove a registered LoaderService.LoaderListener callback.

Parameters:

resourceIds - The unique identifier of the resource, not null.

l - The listener to be removed

See Also:

addLoaderListener(LoaderListener, String...)

isResourceRegistered

boolean isResourceRegistered(String resourceId)

Allows to check if a data resource with the given dataId is registered.

Parameters:

resourceId - The unique identifier of the resource, not null.

Returns:

true, if such a data resource is registered.

getResourceIds

Set<String> getResourceIds()

Get a Set of all registered data resource identifiers.

Returns:

a Set of all registered data resource identifiers, never null.

getData

InputStream getData(String resourceId)
                    throws IOException

Access the input stream of the given data resource. This method is called by the modules that depend on the given data item. The method always returns the most current data, either from the classpath or the local cache, depending which flavors are available and recently updated.
The method must be thread safe and can be accessed in parallel. Hereby it is possible that, when an intermediate update of the data by update occurs, that different input stream content is returned.

Parameters:

resourceId - The unique identifier of the resource, not null.

Returns:

The InputStream for reading the data.

Throws:

IOException - if a problem occurred.

loadDataLocal

boolean loadDataLocal(String resourceId)

Explicitly triggers the loading of the registered data, regardless of its current LoaderService.UpdatePolicy configured, from the fallback/local resource.

Parameters:

resourceId - The unique identifier of the resource, not null.

Returns:

true if load was successful.

Throws:

IOException - if a problem occurred.

loadData

boolean loadData(String resourceId)
                 throws IOException

Explicitly triggers the remote loading of the registered data, regardless of its current LoaderService.UpdatePolicy configured.

Parameters:

resourceId - The unique identifier of the resource, not null.

Returns:

true if load was successful.

Throws:

IOException - if a problem occurred.

loadDataAsync

Future<Boolean> loadDataAsync(String resourceId)

Explicitly asynchronously triggers the remote loading of the registered data, regardless of its current LoaderService.UpdatePolicy configured.

Parameters:

resourceId - The unique identifier of the resource, not null.

Returns:

the Future of the load task started, returns Boolean.TRUE if the load was successful (either from remote or from the fallback resource).

resetData

void resetData(String resourceId)
               throws IOException

Explicitly triggers the reset (loading of the registered data from the classpath backup resource).

Parameters:

resourceId - The unique identifier of the resource, not null.

Throws:

IOException - if a problem occurred.